Attempts have been made for many years to develop ways of communicating between humans and other species. Research has enabled the development of interactive devices for communication between apes and humans. Particular success has been achieved with chimpanzees by Sue Savage-Rumbaugh and her colleagues at the Language Research Center in Atlanta, Georgia. See, e.g., "Language Learning in Two Species of Ape," by Sue Savage-Rumbaugh et al., Neuroscience and Biobehavioral Reviews, Vol. 9, pp. 653-665 (1985). The work of Savage-Rumbaugh et al. was designed to study symbol and language acquisition, referential symbol use, and symbolic communication in chimpanzees. Small, two-dimensional lexigram symbols, arranged on a keyboard, are used by chimps and humans to communicate about relevant interactions like finding and sharing food, playing with toys, and even doing household chores. Chimps learn the lexigrams, not by symbolic matching drills using traditional types of reinforcement, but rather by observing humans using the symbols to communicate in a very free-form interaction about daily activities. In a typical session, a chimp and its trainers roam through a forest, and use symbols on a portable keyboard to discuss where they will go next, whom they might visit, and where favorite food items or toys might be hidden. The particular chimp which was the focus of the study by Savage-Rumbaugh et al. appears to understand English at the level of a young child, uses more than a hundred lexigrams in a referential manner, and employs a simple grammar to clarify his communications.
Attempts at interactive communication with other species have not been as successful. This is true even in the case of certain marine mammals, such as dolphins, porpoises and whales, which are well-known as relatively intelligent creatures having a large brain size in comparison with other animals. Furthermore, these animals have heightened sensory abilities, which enable them to navigate underwater by emitting sounds and then detecting the "echoes" of those sounds reflected from objects in or on the water. This ability to "echolocate" objects is similar to the electronic sonar used by submarines and ships to detect the location of nearby objects (e.g., other ships) in or on water. However, dolphins, porpoises and whales can use this ability to discriminate among objects having different shapes, sizes, densities, and textures, including complex two-dimensional and three-dimensional forms. Moreover, it is also known that these creatures can visually distinguish among two and three dimensional objects having different shapes, including those having different intensities of light and levels of brightness, and can auditorily distinguish different sounds. Nevertheless, in spite of their relative intelligence and heightened sensory abilities, communications between marine mammals and humans have been limited by the lack of a common symbolic medium for facilitating communication.
All training of marine mammals such as dolphins must involve some form of communication. In traditional reinforcement training, humans communicate their expectations, and respond appropriately (e.g., by providing a reward), when the dolphin appears to comprehend and performs the desired action. For example, an upsweep of the trainer's arm sends the dolphin off on a spectacular leap, which can then be followed by the offer of a suitable reward, such as a fish or other food. However, this type of communication is generally only one-way, consisting primarily of commands from human to dolphin concerning the performance of a desired activity or task.
Human trainers have noticed that dolphins often appear to attempt to communicate with humans and influence their behavior by using, for example, squawks and jaw claps. However, the information offered by the animals may appear very ambiguous and quite limited in scope.
Attempts to facilitate unidirectional human-to-dolphin communications have included work with artificial gestural and auditory languages conducted at the Kewalo Basin Marine Mammal Lab (KBMML) by Herman et al. during the 1980's. See, e.g., "Receptive Competencies of Language-Trained Animals," by Louis M. Herman, Advances in the Study of Behavior, Vol. 17, pp. 1-60 (1987). This work made use of traditional reinforcement training to study dolphins' ability to understand language. At KBMML, humans trained dolphins to comprehend gestural as well as acoustic symbols for objects, actions, and modifiers. The dolphins' performance in this training indicated an understanding of the effect of order on the meaning of a string of symbols.
Although the KBMML work demonstrated that dolphins were capable of more than simple conditional discrimination and sequence learning, it was not conducive to communication of information pertaining to social interactions between individual dolphins, or between humans and dolphins. The symbol strings were given one-way, from humans to dolphins, and functioned as commands to execute arbitrary actions with artificial objects which, outside of this context, generally held little interest for the dolphins.
Therefore, the need exists for an apparatus and method to enable marine mammals to learn symbolic communication skills, particularly those which label social interactions, and to provide a means for facilitating the use of such symbols for communications among marine mammals and between marine mammals and humans.